UBIFS crash in power cutting test

[Rock Lee]

> I suspect a bug in the UBIFS xattr code. I saw such a report some
> time ago but the reporter disappeared before I was able to hunt to the issue down.
>
> When you face the crash, is is persistent or does it go away after a reset?
> If it stays, can you share me the filesystem?

Yes, it is persistent, this image(/dev/mtd18 dd image) is about 25MB,
how do I share it with you?